The SIG Beat



Human plasma contains an abundance of circulating extracellular vesicles (EVs) that regulate biological processes and contribute to the pathogenesis of diseases. EVs are promising candidates for development as therapeutic and diagnostic targets. The study of sub-micrometer biological particles, especially sub–100 nanometer exosomes, poses substantial technical challenges as well as opportunities for innovation. The EVIG aims to promote collaboration and knowledge sharing among NIH scientists who are studying EVs, with the goal of accelerating the advancement of the study of EVs in the NIH community and more broadly.

The EVIG will meet quarterly, with the first meeting scheduled for September. Meetings will feature talks related to exosomes, microvesicles, and other EVs, as well the methodologies and approaches used to address biological hypotheses about EVs. The meetings, as well as a LISTSERV (EVIG-L), will provide a forum for sharing best practices (protocols and standards) and for the mentoring and professional development of trainees who are interested in EV-related studies. To join the LISTSERV, visit or contact Jennifer Jones,


The NIH Hispanic Health Research SIG has been established to foster discussions on Hispanic health–related research topics. Topics will include the mechanisms of disease that commonly affect Hispanics and other populations, interventions to prevent chronic diseases or their complications, translational and implementation research, clinical trials, health education and communication, health services–related research, social sciences, bioethics, health policy, and more. These discussions aim to translate knowledge and research into the improvement of the health of Hispanics and the general population, identify new areas of research as well as potential trans-NIH or trans–Department of Health and Human Services (HHS) collaborations.

Larissa Avilés-Santa (NHLBI), Jill Koshiol (NCI), and Ranganath Muniyappa (NIDDK) are the SIG’s co-chairs. The monthly meetings will feature experts from outside and within the NIH and HHS community; the format will range from open discussion of research questions/hypotheses to formal lectures. Upcoming topics include pharmacogenetics; the relationship between risk and protective factors and development of chronic diseases among Hispanics and Latinos of different ancestries; and common pathways for the development or prevention of chronic diseases. There will also be biannual half-day meetings to provide updates on NIH and HHS research activities.

To join the LISTSERV (HISP_HEALTH_RES_INTRST_L), visit For questions, contact Larissa Avilés-Santa at or Ligia Artiles at


The IDIG will bring together scientists at all experience levels with an interest in inflammatory disease research. Inflammation is a complex biological response that occurs in all tissues of the body, typically in response to harmful stimuli (pathogens or irritants) or after repeated mechanical injury. Genetics play an additional role. Although inflammation can be a protective response, if the causative agent is persistent or the mechanisms that regulate the initiation, maintenance, or resolution of the inflammatory response become dysregulated, the inflammation can evolve into a pathophysiological response as is seen in chronic autoimmune, neurodegenerative, fibrotic, and allergic diseases. Inflammation is also a central driver of tumor progression.

The purpose of this SIG is to encourage better communication, thoughtful discussions, and NIH-wide collaboration so that new treatment modalities might be developed for the many chronic inflammatory and fibrotic diseases that affect human health. The group will convene daylong symposia, two or three times a year, on various inflammatory-disease topics and host a bimonthly seminar series focused on basic and translational aspects of inflammation. The group is open to all persons within NIH and associated agencies (FDA, USDA, etc.) who share an interest in basic and translational inflammation research. To join the LISTSERV (INFLAM-DIS-L), visit or contact Thomas A. Wynn at


A Report from the Natural Products SIG


Many natural products are turning out to be promising treatments for human diseases. The Natural Products Scientific Interest Group (SIG) aims to showcase the work of researchers who are making discoveries in the natural-products arena. On May 22, German researcher Ruth Brack-Werner presented her research at one of the SIG’s seminars, held in Lipsett Amphitheater (Building 10). Brack-Werner, a scientist at the German Research Center for Environmental Health in Neuherberg, Germany, is developing anti–human immunodeficiency virus (HIV) drugs and other antiviral drugs from natural sources.

Ruth Brack-Werner


The NIH Natural Products SIG invited German researcher Ruth Brack-Werner to present her research on using natural sources to develop anti-HIV and other antiviral drugs.

Brack-Werner and her colleagues are especially interested in investigating natural products that are sold as herbal medicines or dietary supplements for two reasons: There’s already clinical and safety information available for some, and some products are known to have activity against viruses.

Her group developed a screening method called EASY-HIT (for exploratory assay system for the discovery of HIV inhibitors) that uses a HeLa cell line—engineered to express the genes for two HIV proteins that represent different stages of the viral replication cycle—as well as a red fluorescent reporter gene. Substances can be screened for inhibitory activity against HIV and according to whether they inhibit early or late stages of the viral replication cycle.

More than 25,000 compounds have been screened so far with the method, and the best hit is a natural product that has high activity and a new mode of action. (The information on this product is still confidential.) Using EASY-HIT, the researchers have identified other novel anti-HIV agents including an extract from the marine brown alga Lobophora variegata that inhibits HIV when it enters cells and an extract from the South African medicinal plant Pelargonium sidoides that inhibits the attachment of HIV to cells.

Brack-Werner’s laboratory has also focused on another medicinal plant (called Ci here because the data are not yet published), which grows in the Mediterranean region. Ci is available as a tea and an herbal medicine in Germany and is known to inhibit the influenza virus. Commercial products made from this plant and extracts from laboratory-grown plants were found to have anti-HIV activity by inhibiting viral entry into cells. Efforts are currently being made to isolate the most active fractions of the Ci extracts.

“I’m intrigued by the research Dr. Brack-Werner and her group are doing,” said John Williamson, a branch chief in the National Center for Complementary and Integrative Health. “Her research illustrates the great potential of natural products to help solve some of our toughest medical challenges.”

• M. Helfer, H. Koppensteiner, M. Schneider, S. Rebensburg, S. Forcisi, C. Müller, R. Brack-Werner, et al., “The root extract of the medicinal plant Pelargonium sidoides is a potent HIV-1 attachment inhibitor,” PLoS One 9, e87487 (2014).
• S. Kremb, M. Helfer, W. Heller, D. Hoffmann, H. Wolff, A. Kleinschmidt, R. Brack-Werner, et al., “EASY-HIT: HIV full-replication technology for broad discovery of multiple classes of HIV inhibitors,” Antimicrob Agents and Chemother 54, 5257 (2010).
• S. Kremb S, M. Helfer, B. Kraus, H. Wolff, C. Wild, M. Schneider, R. Brack-Werner, et al., “Aqueous extracts of the marine brown alga Lobophora variegata inhibit HIV-1 infection at the level of virus entry into cells,” PLoS One 9:e103895 (2014).

To join the Natural Products SIG’s LISTSERV, go to To read an article about this SIG that appeared in the July-August 2013 NIH Catalyst, go to